Stacker crane



May 10, 1966 M. J. DECHANTSREITER STACKER CRANE Filed Dec. 24, 1964 5 Sheets-Sheet l INVENTOR. MAX 1 DECHANTSREITER 4 Arvsmj 77% y 1966 M. J. DECHANTSREITER 3,250,399

STACKER CRANE 5 Sheets-Sheet 2 Filed Dec. 24, 1964 INVENTOR. MAX J. DE CHANTJREITER 4 A'f'foRrvEY y 1966 M. J DECHANTSREITER 3,250,399

STACKER CRANE 5 Sheets-Sheet 5 Filed Dec. 24, 1964 INVENTOR. MAX J. DE CHANTSRE I TER AffoRuEY May 10, 1966 M. J. DECHANTSREITER 3,

STACKER CRANE Filed Dec. 24, 1964 5 Sheets-Sheet 4 INVENTOR. MAX J. DECHANTSRE/TER y 1966 M. J DECHANTSREITER 3,

STACKER CRANE 5 Sheets-Sheet 5 Filed Dec. 24, 1964 INVENTOR. HA NTSRE IT 5!? MAX J. DEC

AfroRNEY United States Patent 3,250,399 STACKER CRANE Max J. Dechantsreiter, Milwaukee, Wis., assignor to Haruischfeger Corporation, West Milwaukee, Wis., a corporation of Wisconsin Filed Dec. 24, 1964, Scr. No. 420,908 8 Claims. (Cl. 212-21) The present invention relates generally to material handling devices and, more particularly, to traveling cranes supported by overhead rails and having a vertical, rigid, telescoping mast on which a load carriage is vertically movable. These devices are sometimes referred to as stacker cranes.

Cranes of the type to which the present invention re-' lates are often of considerable size and have an operators cab attached to the load carriage so as to be vertically positionable therewith. Prior art devices of this character have utilized broken rope safety apparatus which prevents the load mast and operators cab from falling in the event of failure or breakage of the hoisting means, particularly the cables.

These prior art devices have several shortcomings. For example, in the event of breakage of a hoisting cable, the falling load and operators cab is suddenly arrested by being locked in place by the conventional safety broken rope devices. This imposes an additional and tremendous load on the entire supporting structure, such as the crane bridge or even the building. In large capacity cranes, the safety devices which would be necessary in order to stop the falling load within a short distance would necessarily have to be of such size as to make it practically impossible to physically be incorporated in the mast structure.

Another disadvantage of these prior art devices is that it is often desired to place the load downwardly into a trench, box car, or other restricted area, and the operators cab which occupies additional space, precludes the free or unrestricted operation of the mast assembly, because it is vertically adjustable therewith.

Accordingly, one aspect of the present invention provides an overhead traveling crane of the vertical, telescoping mast type, which has an independently suspended and vertically adjustable operators cab. The arrangement is such that the mast assembly and operators cab are each vertically adjustable relative to and independently of the other. As a result, the mast assembly can be maneuvered into relatively small areas and/ or down into lower depths that the cab can or need be lowered. Stated otherwise, with the present invention, the load and cab vertically adjusted together, the load can be lowered while the cab remains elevated and stationary, or the load can be left elevated and the cab lowered to permit the operator to get out and inspect the loading area.

Furthermore and importantly, with the present invention which provides independent suspension and operation of the cab, in the event of failure of a hoisting part, such as a cable, the cab only can be held in place and prevented from falling by a broken rope safety device, and the load can be permitted to drop to the ground Without imposing a damaging load on the crane.

These and other objects and advantages of the present invention will appear hereinafter as this disclosure progresses, reference being had to the accompanying drawings, in which:

FIGURE 1 is an elevational view of a stacker crane ice made in accordance with the present invention, certain parts being shown as broken away or in section for clarity in the drawing, and the crane shown in the full retracted or up position;

FIGURE 2 is a plan view of the crane shown in FIG- URE 1, certain parts being shown as broken away;

FIGURE 3 is a section view taken along line 3-3 in FIGURE 1 on an enlarged scale;

FIGURE 4 is an elevational view of a portion of the crane shown in FIGURE 1, taken from line 4-4 in FIGURE 1, certain parts being removed for clarity;

FIGURE 5 is a cross sectional view taken along line 55 in FIGURE 2, but on an enlarged scale;

FIGURE 6 is a diagrammatic view of the primary cable lifting system;

FIGURE 7 is a diagrammatic view of the lifting means for the operators cab;

FIGURE 8 is an enlarged, fragmentary view of a portion of the upper end of the cab mast shown in FIG- URE 1, with certain parts removed for clarity;

FIGURE 9' is a view taken along line 99 in FIG- URE 8, certain parts being removed or broken away for clarity;

FIGURE 10 is a sectional view taken along line 1il10 in FIGURE 8; and

FIGURE 11 is a view of a portion of FIGURE 9, but showing the cab in the mast locking position.

Referring in greater detail to the drawings, a pair of overhead rails 1 and 2 are provided in spaced apart relationship and on which the entire crane C is supported for travel between the rails. These rails are suitably mounted in any conventional manner, not shown, as for example, as part of an overhead runaway structure or building structure.

Trolley frame A trolley T has a series of wheels 3 which ride along and are guided by rails 1 and 2, the wheels being suitably journalled in the two parallel, frame members 4 and 5. A large, rectangular, steel plate 6 is welded across the upper sides of member 4 and 5 and other steel plates 7 and 8 are also Welded to members 4 and 5, all forming a rigid trolley frame. The trolley is driven along the rails in either direction by an electric motor 9 through the drive box 9a and the drive shaft 912 on which some of the wheels 3 are fixed. A brake 9c is also provided for the motor.

The trolley also includes a large circle or ring 10 which, as shown clearly in FIGURE 5, is comprised of an upper ring plate 10a and a lower, ring plate 10b parallel thereto an inner, vertical ring wall 10c and an outer vertical ring wall 10d, all welded together to form the ring 10 having a rectangular cross sectional shape.

The ring 10 is secured to the horizontal plate 6 of the trolley frame by a series of eight horizontal bars 12, two on each side of the frame, as clearly shown in FIGURE 2. These bars are secured by nuts 13 to brackets 14 Welded to the plate 6, and to brackets 15 weldedto the periphery of ring 10. By this means the ring 10 is prevented from moving horizontally relative to plate 6.

Means are also provided, as will now be described, for vertically supporting the ring 10 on plate 6 in such a manner that the load on the crane can be weighed.

Four load weighing cells 17 are located in circumferentialy spaced relationship on top of plate 6 and the plates 18 of the ring 10 rest on top of these cells. Thus strict downward, weighing movement of the ring relative to plate 6.

Turntable A turntable 20 is carried on the trolley frame for rotation about a central, vertically disposed axis. This turntable carries a downwardly depending mast assembly which will be described later and which rotates together with the turntable as a single unit about this vertical axis.

The turntable includes a large, horizontal, circular steel plate 21 which is rotatably supported by the large, anti-friction, bearing ring assembly 22 located on the top of ring 10. Assembly 22 includes an inner race 22a secured to the underside of the turntable, an outer race 22b secured to the upper side of ring 10, and a series of balls 22c located between the races in the conventional manner to carry vertical and horizontal thrust components.

Located on top of the turntable is the conventional electric motor 23 connected by the drive reduction unit 24 to the cable drum 25. A brake 26 is located between the motor and drum, and an eddy current brake 27 is connected with the motor, for purposes that will appear later.

Mast assembly A mast assembly 30 is rigidly fixed to the underside of the turntable and extends downwardly therefrom. The mast assembly includes rigid mast R welded to an upper plate 29 and two large gusset plates 31, 32 are welded between mast R and plate 29 for rigidity and reinforcement. Plate 29 is then in turn rigidly secured to turntable plate 21 by bolt means 29a. The assembly also includes a shorter, intermediate mast I which slides up and downon the long mast R, and also includes a load mast L which can be vertically positioned relative to the intermediate mast. As shown in FIGURE 3, these masts are rectangular in cross section and nested together in telescoping relationship. More specifically, a pair of rollers 33 are mounted by bolt means 34 along each of the opposite sides of the load mast R and are held captive and guided in their vertical movement by the pairs of rails 35 (FIGURE 3 and 4) fixed to the opposite sides of intermediate mast R. Similarly, a pair of rollers 36 are mounted by bolt means 37 along each of the opposite sides of load mast L for being guided by the pairs of opposed rails 38 fixed to the opposite sides of the intermediate mast I. I

Other pairs of rollers 44 (FIGURE 4) are mounted on the opposite sides of the load mast about horizontal axes and rotate in abutting relationship with the intermediate mast to provide guiding and stabilizing therebe tween in a direction parallel to the axis of rollers 36. Reinforcing gusset plates 45 are welded to the mast L and to the bracket mounting 44a for rollers 44.

The load mast may have a lift fork unit vertically adjustable along the pair of vertical rails 51 by means of a hydraulic cylinder 52 connected between the unit 50 as at 52a (FIGURE 4) and the load mast as at 52b. The rails 51 are of T shape cross section and are welded along their length to the load mast.

Power lift A cable lifting system is provided directly between the load mast L and the rigid mast R. This multiple-sheave system imposes the entire load directly on the turntable without going through the intermediate mast I. This 4 system is shown diagrammatically or in a spread out manner in FIGURE 6.

More specifically, a plurality of sheaves 60 are rotatably mounted on'the upper end of the rigid mast R and a plurality of sheaves 62 is also rotatably mounted directly on the load mast L. A cable 63 is attached to the drum 25 at each of its ends and trained around sheaves 60 and 62 as shown.

As shown in FIGURES 1 and 4, there is also provided a flexible member connection between the three masts R, I and L but this connection does not perform any function of lifting the load. Instead it serves to transmit the Weight of the intermediate mast I to the rigid mast,

and keeps the intermediate mast in proper relationship to the load mast and rigid mast.

This flexible member connection includes a pair of sheaves 65, 66 rotatably mounted at the lower end of the intermediate mast I, having a cable 67, 68, respective ly, trained therearound. These cables 67 and 68 are deadended to the rigid mast R at 69 and 70, respectively, and to the load mast at 71 and 72, respectively. This system insures that the relative proportionate vertical speed between the load mast and intermediate mast remains the same. For example, if the load mast moves at ten feet per second, then the intermediate mast will move at one-half that speed, namely, five feet per second.

The present arrangement requires only one cable lift system to carry the entire load and only a lightweight flexible lift connection is required to support the intermediate mast and coordinate its movement with the load mast.

Operator's cab-FIG URES 1 and 3 In accordance with another aspect of the present invention an operators cab 0C is provided which is both suspended and vertically adjustable independently of the mast assembly, more particularly of the load itself.

The cab mast assembly is shown in FIGURE, 1 in the fully retracted or up position and is shown for illustrative purposes only as comprising two telescoping mast members, namely, a fixed inner mast rigidly secured at its upper end to the rigid mast and which extends downwardly to terminate at 80a. The second member is an outer mast 82 which telescopes over the inner mast. The cab is rigidly attached to the outer mast for vertical movement therewith.

The members 80 and 82 are mounted together as follows. Guide rails 84 are secured one along the length of each of the opposite outer sides of the inner mast. Pairs of rollers 85 are mounted on the inside of each of the opposite sides of the outer mast and these rollers engage opposite sides of the adjacent rail.

Other rollers 88, disposed on axes ninety degrees to those of the rollers 85, are rotatably mounted on opposite sides of the outer mast 82 and roll against the rails 84. By means of these rollers 85 and 88, guiding support in all directions is provided between the inner and outer masts as they telescope relative to one another.

FIGURE 7 is a schematic diagram of the lifting arrangement for the cab. The cab is vertically positioned by a hoist drum (FIGURE 1) mounted on the trolley frame and two sheaves 91 and 92 mounted on the outer mast 82. A pair of cables 93 and 94 are fixed at one of their ends to the drum, and are then trained around the sheaves 91 and 92 and then deadended to an equalizer bar 95. Bar 95 is pivotal mounted at 96 on the trolley frame. Stops 92a and 96b prevent excessive movement of the bar 95. A measure of safety is provided by the use of two cables and an equalizer bar because,

in the event one cable breaks, the other will hold the cab.

Furthermore, broken rope safety devices for the load are not necessary to insure safety of the operator. If a load cable breaks, it is not necessary to catch a twenty-five ton falling load for example, and instead the load can be permitted to fall without damaging the crane and/or its supporting structure.

Cab safety device A broken rope safety device is provided for catching the operators cab in the event a hoist cable breaks, and this device is shown in detail in FIGURES 8 and 9. The mounting for each of the sheaves 91 and 92 is similar and one will be described. A sheave bracket 97 is pivotally mounted on the shaft 98 fixed on the upper end of mast member 82. Brackets 97 have slots 99 in each of their slides through which a bar 100 extends loosely. Bar 100 is welded to the upper end of mast 82 and is normally contacted by microswitches 101 and 102 carried on the sheave brackets.

If the cable 91 is not broken and the cab mast operating normally, the brackets are pulled upwardly against the bar 100. If the cable 93 breaks, either one or both of the brackets 97 instantly drops, carrying the switches with them and away from contact with bar 100. This action opens either one or both of the switches which in turn de-energizes solenoids 104. De-energizing of a solenoid causes downward shifting of its link 105 and causes its cam 106 to be rotated from the mast unlocked position shown in FIGURE 9 to the mast locked position shown in FIGURE 11. When the cams are in the FIGURE 11 position, they bind or lock against the inner mast member 80 and lock the outer mast member 82 thereagainst it. The cams are suitably journaled on their shaft 107 and extend through slots 108 in the outer mast member 82. An overtravel slot 109 is provided in link 105 and arm 110 fixed to shaft 107 has a pin 111 fixed thereto which travels in this slot. Thus, the solenoid 104 can return freely to its normally energized position. Spring 112 returns the cam to its normal running, unlocked position where its flat, clearance portion 113 permits free movement between the mast members 80 and 82,

With the above described cab arrangement, greater maneuverability of the mast assembly is possible, the operator can he more selective in choosing an advantageous height of operation, and greater safety and flexibility of operation is provided. As well as moving the cab together with the load, it can be completely independent thereof for any combination of relative movements.

Various modes of carrying out the invention are contemplated as being within the scope of the following particularly pointing out and distinctly claiming the subject matter which is regarded as the invention:

1. An overhead traveling stacker crane including a travelling trolley, said trolley having a downwardly extending mast assembly for vertically positioning a load carried thereby, a separate and telescopingly extensible rigid cab mast carried by and extending downwardly from said trolley, a cab mounted on said cab mast for vertical movement, means on said trolley for vertically adjusting the position of said cap, and a safety device on said cab mast for arresting falling movement of said cab.

2. A crane as defined in claim l further characterized 4 in that said means can adjust said cab independently of the vertical adjustment of said mast assembly.

3. An overhead traveling crane having a turntable mounted on said crane for rotation about a vertical axis, an extensible mast assembly rigidly secured to said tumtable for rotation therewith and extending downwardly therefrom for vertically positioning a load carried on said assembly, a separate and extensible cab mast carried by and extending downwardly from said turntable for rotation therewith, a cab mounted on said cab mast for vertical movement, means on said crane for vertically adjusting the position of said cab, and a safety device on said cab mast arresting falling movement of said cab.

4. An overhead traveling stacker crane including a travelling trolley, said trolley having a downwardly ertending mast assembly, power lift means between said trolley and said mast assembly for extending and retracting thereof and vertically positioning a load carried thereby, a separate and telescopingly extensible rigid cab mast carried by and extending downwardly from said trolley and alongside but free of said mast assembly, a cab mounted on said cab mast for vertical movement independently of said extension and retraction of said mast assembly, power lift means on said trolley for vertically adjusting said extensible cab mast and consequently the position of said cab, and a safety device on said cab mast for arresting falling movement of said cab.

5. An overhead traveling crane having a turntable mounted on said crane for rotation about a vertical axis, an extensible mast assembly rigidly secured to said tumtable for rotation therewith and extending downwardly therefrom, power lift means between said crane and said mast assembly for extending and retracting thereof and vertically positioning a load carried on said assembly, a separate and extensible cab mast carried by and extending downwardly from said turntable for rotation therewith, a cab mounted on said cab mast for vertical movement, other power lift means on said crane for vertically adjusting said extensible cab mast and consequently ,the position of said cab, and a safety device on said cab mast for arresting falling movement of said cab.

6. An overhead traveling crane having a turntable rotatably mounted about a vertical axis, a telescoping mast assembly secured to and extending downwardly from said turntable for vertically positioning a load carried by said assembly, said assembly comprising a rigid mast secured to said turntable, an intermediate mast mounted on and vertically movable relative to said rigid mast, a load mast having means to support a load, said load mast mounted on and vertically movable relative to said intermediate mast, power lift means on said turntable and directly connecting said rigid mast and said load mast for imposing the weight of the load directly on said rigid mast and effecting vertical movement of said load mastj a flexible lift connection between said intermediate mast, said rigid mast, and said load mast, and a separate and extensible cab mast secured to and extending downwardly from said turntable, a cab mounted on said cab mast for vertical movement, lift means on said turntable for vertically adjusting the position of said cab, and a safety device on said cab mast for arresting falling movement of said cab.

7. A crane as defined in claim 6 wherein said lift means on said turntable is separate from said power lift means for said mast assembly.

8. An overhead traveling crane having a turntable mounted on a vertical axis and telescoping mast assembly secured to and extending downwardly from said turntable for vertically positioning a load carried by said assembly, said assembly comprising a rigid mast secured to said turntable, an intermediate mast mounted on and vertically movable relative to said rigid mast, a load mast having means to support a load, said load mast mounted on and vertically movable relative to said intermediate mast; power lift means connected directly between said rigid mast and said load mast for imposing the weight of the load directly on said rigid mast and effecting vertical movement of said load mast, said power lift means comprising sheaves mounted on said rigid mast and on said load mast, a power winch drum on said turntable, and a flexible cable trained around said drum and sheaves; and a sheave and cable connection between said intermediate mast, said rigid mast, and said load mast, whereby vertical movement of said load mast causes telescoping vertical movement of said intermediate mast over said rigid mast and in the same direction as said load mast but at a lower speed, and a separate and extensible cab mast secured to and extending downwardly from said turntable, a cab mounted on said cab mast for vertical movement, and lift means on said turntable for vertically adjusting the position of said cab, and a safety device on said cab mast for arresting falling movement of said cab.

References Cited by the Examiner UNITED STATES PATENTS Heinle.

Pevear 21221 Ringe 212-21 Schellentrager 214-2 Geist 212-135 Dehn 21221 Riemenschnider 212135 Hofimeister 2142 Valliere et a1. 212128 EVON C. BLUNK, Primary Examiner.

HUGO O. SCHULZ, Examiner.

A. L. LEVINE, Assistant Examiner. 

1. AN OVERHEAD TRAVELING STACKER CRAND INCLUDING A TRAVELLING TROLLEY, SAID TROLLEY HAVING A DOWNWARDLY EXTENDING MAST ASSEMBLY FOR VERTICALLY POSITIONING A LOAD CARRIED THEREBY, A SEPARATE AND TELESCOPINGLY EXTENSIBLE RIGID CAB MAST CARRIED BY AND EXTENDING DOWNWARDLY FROM SAID TROLLEY, A CAB MOUNTED ON SAID CAB MAST FOR VERTICAL 